Mechanisms of disease
How disease happens — pathology, pharmacology, microbiology. 33 questions.
A 46-year-old man develops jaundice, dark urine and exertional dyspnoea over several weeks. He has splenomegaly, a haemoglobin concentration of 78 g/L (130–170)…
Haematology and Oncology · Mechanisms of disease · common
A 30-hour-old boy develops jaundice and pallor. He is feeding reasonably well and has mild splenomegaly. His mother is blood group O positive and he is group B…
Paediatrics · Mechanisms of disease · middle twist
A 26-year-old man is referred for recurrent episodes of yellowing of the eyes, usually after intercurrent illness. He has no pruritus, abdominal pain or weight…
Gastroenterology and Hepatology · Mechanisms of disease · niche
A 67-year-old man with alcohol dependence has mild withdrawal 10 hours after his last drink, with anxiety, tremor and nausea but no hallucinations or seizure. H…
Gastroenterology and Hepatology · Mechanisms of disease · middle twist
A 59-year-old woman develops sharp central chest pain two days after an uncomplicated ST-elevation myocardial infarction. She says it is worse when she takes a…
Cardiovascular · Mechanisms of disease · middle twist
A 34-year-old woman with schizoaffective disorder becomes restless, sweaty and confused six hours after venlafaxine was increased and tramadol was prescribed fo…
Emergency and Toxicology · Mechanisms of disease · common
A 29-year-old woman requests emergency contraception four days after unprotected intercourse. She has a body mass index of 34 kg/m² and takes carbamazepine for…
Obstetrics and Gynaecology · Mechanisms of disease · middle twist
A 48-year-old woman taking sotalol for paroxysmal atrial fibrillation has two brief episodes of collapse. The ECG monitor records recurrent bursts of polymorphi…
Emergency and Toxicology · Mechanisms of disease · common
A 54-year-old woman has progressive exertional dyspnoea. Spirometry shows a forced expiratory volume in one second of 2.4 L (reference greater than 2.0 L) and a…
Biomedical Science · Mechanisms of disease · middle twist
A laboratory technician is found unconscious in a poorly ventilated garage. Arterial blood shows pH 7.39, PaO2 13.0 kPa (reference 10.7–13.3 kPa), and PaCO2 5.1…
Biomedical Science · Mechanisms of disease · common
A 68-year-old man develops sudden pleuritic chest pain and tachypnoea after prolonged immobility. Arterial blood gas analysis on room air shows pH 7.48, PaCO2 3…
Biomedical Science · Mechanisms of disease · common
A 35-year-old woman has palpitations and a 9 kg weight loss over 3 months. Her free thyroxine is 48 pmol/L (reference 10–22 pmol/L), TSH is less than 0.01 mIU/L…
Biomedical Science · Mechanisms of disease · common
A 41-year-old woman has progressive weight gain, proximal muscle weakness and easy bruising. Her 24-hour urinary free cortisol is 780 nmol/day (reference less t…
Biomedical Science · Mechanisms of disease · middle twist
A 29-year-old woman has a plasma bicarbonate concentration of 15 mmol/L (reference 22–29 mmol/L) and a normal anion gap. Her urine pH is 6.2 during bicarbonate…
Biomedical Science · Mechanisms of disease · middle twist
A healthy adult receives an intravenous glucose load. Plasma glucose is 12 mmol/L (reference 3.5–7.8 mmol/L), the measured glomerular filtration rate is 120 mL/…
Biomedical Science · Mechanisms of disease · common
A 48-year-old woman has a new holosystolic murmur and exertional dyspnoea. Echocardiography shows a regurgitant volume from the left ventricle into the left atr…
Biomedical Science · Mechanisms of disease · common
A 62-year-old man undergoes left ventricular pressure-volume loop analysis during cardiac catheterisation. Before an intervention, his end-diastolic volume is 1…
Biomedical Science · Mechanisms of disease · common
A 70-year-old man presents with dysuria, a slow urinary stream, and a feeling of incomplete emptying. Urinalysis shows leukocytes and nitrites. He is afebrile a…
Year 1 · Mechanisms of disease · common
A 21-year-old woman presents to the GP with urinary urgency, suprapubic discomfort, and dysuria. This is her third similar episode in the past year. She does no…
Year 1 · Mechanisms of disease · middle twist
A 45-year-old woman presents with a painful, swollen, red area on her right forearm that developed over the past two days. She reports a minor cut from gardenin…
Year 1 · Mechanisms of disease · common